Electromagnetic tooth-stopping hammer.



Patented Oct. 30, I900.

' O. OSTMANN.

ELEOTROMAGNETlO TOOTH STOPPING HAMMER. (Application filed Juno 5, 1899.)

(No Modal.)

TNE NORRIS Perms 00., PNOYO-LITNQ, WASHKNGYQN. m c.

' UNITED STATES PATENT OFFICE.-

CURT OSTMANN, OF BRESLAU, GERMANY.

ELECTROMAGNETIC TOOTH-STOPPING HAMMER.

SPECIFICATION forming part of Letters Patent No. 660,867, dated October 30, 1960;

Application filed June 5,1899. Serial No. 719A1Z. (No model.)

To all whom it may concern.-

Be it known that I, CURT OSTMANN, a subject of the King of Prussia, Emperor of Germany, residing at Breslau, in the Kingdom of Prussia, German Empire, have invented certain new and useful Improvements in Electromagnetic Dental Pluggers, (for which I have applied for patents in Switzerlaud,No. 21,087, dated May 3,1899; in England, No. 9,349, dated May 3,1899; in France, No.276,410, dated May 3,1899; in Belgium, No. 111,847, dated May 8, 1899; in Italy, dated May 3, 1899; in Austria, dated April 29, 1899; in Hungary, No. 6,493, dated May 1, 1899, and in Germany, dated Feb ruary 25, 1899,) of which the following is a specification.

The essential difference between the wellknown Bonwill hammer for fillingin the stopping of teeth and the hammer which is illustrated in the annexed drawing consists in the arrangement of the electromagnet having a twopart core, of which one part carries the gold stopping-point q, while the other serves as the striking part. The construction is of the simplest kind imaginable. It is based on the principle of the well-known electrical hammer, and it is almost impossible for it to' get out of order. The magnet-cores are arranged behind one another in a metal tube, (made, preferably, of aluminium on account of its lightness,) and the consequence of this is that the Weight is distributed in a uniform manner, while the manipulation of theinstrumentis extremely convenient, because it weighs only about ninety grams. The electric current, which is generated by five dry cells (Leclanch cells or the like) enters at Ct and passes through the platinum contact into the spiral, which is electrically connected to the metallic tube ,2 and to the beginning of the coil or winding w. A screw-post connected to the terminal binding-post a car ries at its lower end a spring, as indicated, againstwhich the platinum contact-point carried by the spring-mounted core Z normally abuts. The Winding of the copper wire d, which is insulated by means of silk, begins at w, where the beginning of the wire is soldered to the metal tube and is carried up to the insulated terminal 7;, whence the current returns to the battery. The soft-iron cylinder .1 is held back by a weak springf. The iron cylinder Z is caused when the currentcircuit is completed to make rapid horizontal toand-fro movement, in consequence of which it strikes in rapid succession upon the end 6 of the cylinder w, both becoming electromagnetic. The force of the blows can be regulated by means of a rheostat or cellcounter. The current entering through the terminal a magnetizes both parts of the core, drawing down the core-section Z and delivering a blow to the pluggingtool, the magnetization in both core-sections contributing to this effect.

The opening of the circuit at the platinum contact permits the core Z to rebound, again closing the circuit and delivering another blow.

The main contact for the purpose of setting the instrument inoperation may be provided in the form of a switch on the handle.

What I claim, and desire to secure by Letters Patent of the United States, is

1. A dental plugger comprising an electromagnet provided with circuit-terminals, said electromagnet being provided with a twopart core of magnetizable material, one part adapted to carry a dental tool and the other carrying a circuit-breaking contact, both sec tions being elastically mounted.

2. A dental plugger comprising a shell of non magnetic metal, a magnetizing coil around the same, a two-part iron core, each part being independently and elastically mounted, one adapted to carry a dental tool, and the other provided with a circuit-interrupting contact and adapted to deliver a blow to the other and automatically open the eircuit.

In testimony whereof I have hereunto set my hand in the presence of two witnesses.

CURT OSTMANN.

\Vit nesses:

CARL WEBER, HERMANN BARTSOH. 

